KR20230034946A - Vacuum pumps and cleaning systems for vacuum pumps - Google Patents

Abstract

Provided is a vacuum pump capable of decomposing by-products by radicals into particles and effectively discharging them to the outside. An outer cylinder 127 having an intake port 101 and an exhaust port 133, a rotor shaft 113 rotatably supported inside the outer cylinder 127, and a plurality of rotary blades fixed to the rotor shaft 113 ( 102), it is a vacuum pump equipped with a rotating body 103 rotatable together with the rotor shaft 113, and at least one radical supply port 201a capable of supplying a plurality of types of radicals into the outer cylinder 127 and A radical supply means 201 for supplying radicals to the radical supply port 201a is provided.

Description

Vacuum pumps and cleaning systems for vacuum pumps

The present invention relates to a vacuum pump and a cleaning system for a vacuum pump, and more particularly, to a vacuum pump and a cleaning system for a vacuum pump capable of removing deposits and the like generated by solidification of gas in a vacuum pump.

In recent years, in a process of forming a semiconductor element from a wafer serving as a processing target substrate, a method of manufacturing a semiconductor element of a product by processing the wafer in a process chamber of a semiconductor manufacturing apparatus maintained in a high vacuum has been taken. In a semiconductor manufacturing apparatus that processes wafers in a vacuum chamber, a vacuum pump equipped with a turbo molecular pump unit and a screw groove pump unit is used to achieve and maintain a high degree of vacuum (see Patent Document 1, for example).

The turbo molecular pump unit has, inside the housing, rotatable rotor blades made of thin metal and fixed blades fixed to the housing. Then, the rotary blade is operated at a high speed of, for example, hundreds of m/s, so that the process gas used for processing coming in from the intake port side is compressed inside the pump and exhausted from the exhaust port side.

By the way, molecules of the process gas drawn in from the intake port side of the vacuum pump are compressed in a process accompanying movement to the exhaust port side accompanying rotation of the rotor blades within the vacuum pump, so that the process gas is solidified and solidified by-products are fixed. It is deposited by adhering to the wing or the inner surface of the outer cylinder. Deposits as by-products of the process gas adhering to the stator blade, the inner surface of the outer cylinder, etc. obstruct the path of gas molecules toward the exhaust port side. For this reason, problems such as a decrease in the exhaust capacity of the turbo molecular pump, an abnormal treatment pressure, and a decrease in production efficiency due to interruption of treatment of the deposits have occurred.

In addition, there has been a problem that particles of the process gas bouncing back from the vacuum pump side flow back into the processing chamber (chamber) of the semiconductor manufacturing apparatus and contaminate the wafer.

As a countermeasure against this, a vacuum pump in which a radical supply device for generating radicals for exfoliating and decomposing deposits adhering to and depositing on the inner surface of a stator blade or an outer cylinder is provided at the inlet of the vacuum pump has also been proposed (for example, patent literature 2).

In the technique known as Patent Document 2, a radical supply unit is provided near an inlet of a vacuum pump, and radicals are ejected from a nozzle of the radical supply unit toward the inner center to supply the radicals.

Japanese Patent Publication No. 2019-82120 Japanese Patent Laid-Open No. 2008-248825

In the invention described in Patent Document 2, radicals from a radical supply unit are discharged from a nozzle in the vicinity of an intake port on the side adjacent to a chamber of a semiconductor manufacturing apparatus or the like, and at the uppermost position of a rotor blade and a stator blade. A configuration in which the jet is blown and supplied toward the inner center is employed. Then, the radicals supplied from the radical supply unit flow together with the process gas through the inside of the outer cylinder toward the exhaust port side, decompose and convert deposits adhering to the stator blades or the inner surface of the outer cylinder, etc. along the way, and are discharged from the exhaust port together with the process gas. It has become a structure to do.

In such a structure in which radicals are supplied from the vicinity of the intake port adjacent to the chamber and from the uppermost position of the rotary blade and stator blade, by-products in the intake port on the inlet side of the vacuum pump react to the radicals, When particles are formed, there is a problem that they flow back into the chamber and cause wafer defects.

In addition, since radicals are unstable substances that forcibly break molecular bonds by applying large amounts of energy to source gas, they recombine in a relatively short time and lose their activity. Therefore, even when supplied from the intake port of the vacuum pump, the radicals recombine and lose activity before reaching the vicinity of the exhaust port of the vacuum pump due to collisions between radicals, collisions with stator blade blades or housings, and the like. Therefore, there is a problem in that the radicals do not spread widely inside the vacuum pump, and thus cleaning cannot be performed effectively.

In addition, when cleaning is performed by supplying radicals, there is also a problem that if the supply of radicals becomes excessive, in addition to decomposition of by-products, components constituting the process chamber and the vacuum pump are deteriorated.

Also, in recent years, by-products such as TiN (tin), which cannot be granulated by a single radical reaction, have come to be seen.

Therefore, a technical problem to be solved arises in order to provide a vacuum pump capable of decomposing by-products into particles by radicals and effectively discharging them to the outside, and an object of the present invention is to solve this problem.

The present invention has been proposed to achieve the above object, and the invention described in claim 1 is a housing having an intake port and an exhaust port, a rotor shaft rotatably supported inside the housing, and a rotation fixed to the rotor shaft. A vacuum pump having blades and a rotating body rotatable together with the rotor shaft, wherein at least one radical supply port capable of supplying a plurality of types of radicals into the housing and a radical supply supplying the radicals to the radical supply port A vacuum pump having means is provided.

According to this configuration, when particles cannot be formed by reaction with a single radical, a plurality of types of radicals are supplied from the radical supply port of the radical supply means, and the by-products capable of being granulated are formed through steps using a plurality of radicals. Sediments can be effectively granulated and discharged.

The invention recited in claim 2 provides the vacuum pump according to claim 1, wherein the radical supply means has a radical generating source adapted to the generation of the different types of radicals and a power supply for driving the radical generating source.

According to this configuration, since the radical supply means has a radical generating source tailored to the generation of different types of radicals and a power supply for driving the radical generating sources, the radical generating source tailored to generating different types of radicals and a power supply for driving the radical generating sources, It is possible to generate different types of radicals, and by using a plurality of radicals, the sediment made of by-products that can be granulated through stages can be effectively granulated and discharged.

The invention recited in claim 3 provides a vacuum pump according to claim 2, wherein at least a part of the power source for driving the different types of radical generating sources is shared with a power source for controlling the pump.

In order to drive each radical generating source of a different type, each power source is required, but if there are multiple power sources, cost increase or lack of space may become a problem. In this configuration, at least a part of the power source is shared with the pump control power source, Effects of cost reduction and space reduction can be expected.

The invention recited in claim 4 provides a vacuum pump according to claim 2, wherein at least a part of the power source for driving the different types of radical generating sources is shared with a power source for plasma generation in the chamber.

In order to drive each radical generating source of a different type, each power source is required, but if there are multiple power sources, cost increase or lack of space may become a problem. In this configuration, at least a part of the power source is shared with the pump control power source, Effects of cost reduction and space reduction can be expected. By sharing the power source for plasma generation in the chamber, effects of cost reduction and space reduction can be expected.

In the invention according to claim 5, in the configuration according to any one of claims 2 to 4, the radical generating source is capable of exchanging electrodes, the power supply of the radical generating source has a voltage output variable function, and various Generation of radicals is feasible by exchanging the electrodes and adjusting the voltage output of the power supply, providing a vacuum pump.

According to this configuration, since the radical generating source can replace electrodes and the power supply has a variable voltage output function, generation of various radicals can be realized by exchanging electrodes and adjusting the voltage output of the power supply.

In the invention according to claim 6, in the configuration according to any one of claims 1 to 5, the radical supply means is provided to correspond to the radical supply ports, respectively, and the radicals supplied from the respective radical supply ports A vacuum pump having a valve capable of controlling supply is provided.

According to this configuration, the supply amount of radicals supplied from each radical supply port can be controlled by a valve provided corresponding to each radical supply port, and a required amount of radicals can be supplied from each radical supply port.

The invention according to claim 7 provides the vacuum pump according to any one of claims 1 to 6, wherein each of the radical supply ports is disposed at a position approximately equidistant from the intake port in the axial direction. do.

According to this configuration, since each radical supply port is disposed at a position substantially equidistant from the intake port in the axial direction, it is easy to adjust the amount and timing of radicals supplied from each radical supply port.

The invention according to claim 8 provides the vacuum pump according to any one of claims 1 to 6, wherein the vacuum pump further includes a controller that controls opening and closing of the valve.

According to this structure, adjustment of the quantity and timing of the radical supplied from each radical supply port can be performed simply through a controller. Further, in this controller, a signal from an external device (for example, a semiconductor manufacturing device) can be received, and radicals can be optionally supplied into the vacuum pump.

The invention recited in claim 9 provides the vacuum pump according to claim 8, wherein the controller controls opening and closing of the valve based on operation data indicating an operation status of the vacuum pump.

According to this configuration, the controller itself can judge the state of the vacuum pump from the operation data of the vacuum pump and automatically supply radicals into the vacuum pump.

In the invention according to claim 10, in the configuration according to claim 9, in the controller, when the current value of the motor that rotates and drives the rotor shaft, which is the operation data, exceeds a predetermined threshold value, by-product accumulation proceeds, A vacuum pump is provided which determines that the supply of the radical is necessary for cleaning the by-product.

According to this configuration, when the current value of the motor that rotates and drives the rotor shaft, which is the operation data, exceeds a predetermined threshold value, the accumulation of by-products is progressing, and the controller determines that supply of radicals is necessary for cleaning the by-products. By judging, it is possible to automatically supply radicals into the vacuum pump.

In the invention according to claim 11, in the configuration according to claim 9, the controller operates the valve when the current value of the motor that rotates and drives the rotor shaft, which is the operation data, is substantially equal to the current value of the motor during no-load operation stored in advance. A vacuum pump is provided that controls the opening and closing of the

According to this configuration, the controller itself compares the current value of the motor during no-load operation with the current value of the vacuum pump with respect to the current value of the vacuum pump, and when the current value of the motor during no-load operation is approximately equal to the current value of the motor, the inflow of the process gas is stopped. It is judged that there is no, and radicals can be automatically supplied into the vacuum pump.

In the invention according to claim 12, in the configuration according to claim 9, the controller determines that, when the pressure value of the vacuum pump, which is the operation data, exceeds a predetermined threshold value, accumulation of by-products is progressing, and the by-products A vacuum pump is provided that determines that supply of the radicals is necessary for cleaning.

According to this configuration, the controller itself judges the accumulation state of by-products in the vacuum pump from the pressure value of the vacuum pump, determines whether radicals are needed to be supplied into the vacuum pump for cleaning the by-products, and vacuums when necessary. Radicals can be automatically supplied into the pump.

In the invention according to claim 13, in the configuration according to claim 9, the controller operates the valve when the pressure value of the vacuum pump, which is the operation data, is substantially equal to the pre-stored pressure value of the vacuum pump during no-load operation. A vacuum pump that performs open/close control is provided.

According to this configuration, the controller itself compares the pressure value during no-load operation with the current pressure value of the vacuum pump with respect to the pressure value of the vacuum pump, and when the pressure value of the vacuum pump during no-load operation is approximately the same, the pressure value of the process gas It is determined that there is no inflow, and radicals can be automatically supplied into the vacuum pump.

The invention according to claim 14 is a rotating body having a housing having an intake port and an exhaust port, a rotor shaft rotatably supported inside the housing, and a rotor blade fixed to the rotor shaft, and being rotatable together with the rotor shaft. A cleaning system for a vacuum pump having at least one radical supply means capable of supplying a plurality of types of radicals into the housing.

According to this system configuration, when particles cannot be formed by reaction with a single radical, a plurality of types of radicals are supplied from the radical supply port of the radical supply means, and a plurality of radicals are used to form by-products capable of being granulated through steps. The formed sediment can be effectively granulated and discharged.

According to the invention, since a radical supply port capable of supplying a plurality of types of radicals into the housing and a radical supply means for supplying radicals to the radical supply port are provided, in the case where particles cannot be formed by the reaction of a single radical, the radical supply means A plurality of types of radicals are supplied from the radical supply inlet, and deposits made of by-products capable of being granulated are effectively granulated and discharged through steps using the plurality of radicals, thereby performing cleaning treatment.

In addition, by supplying radicals into the vacuum pump, since it is possible to supply radicals in an amount necessary and sufficient for reacting by-products in the vacuum pump, it is possible to minimize deterioration of the material itself of the vacuum pump, and to generate radicals. The supply amount of the necessary gas can also be reduced to a minimum.

In addition, when each radical supply port is formed by positioning it on the exhaust port side of the stator blade closest to the inlet port in the axial direction of the rotor shaft, a part of the particles reacted with radicals and become particles is directed to the inlet port side (chamber side). When trying to return, some of the particles heading toward the inlet port side are prevented from heading toward the inlet port side by causing them to collide with the stator blades disposed on the inlet port side, so that some of the particles can be suppressed from returning to the inlet port side. It becomes possible to reduce the defect rate in a manufacturing apparatus etc.

In addition, since by-products can be formed into particles by radicals and discharged from the inside of the vacuum pump, there is no need to stop the semiconductor manufacturing equipment and clean, repair, or replace the vacuum pump, thereby improving the production efficiency of semiconductors, Cleaning, repair and replacement costs can be reduced.

1 is a longitudinal sectional view of a turbo molecular pump shown as an example of a vacuum pump according to an embodiment of the present invention.
Fig. 2 is a diagram showing an example of an amplifier circuit in the above turbo molecular pump.
3 is a time chart showing a control example in the case where the current command value detected by the amplifier circuit in the above turbo molecular pump is greater than the detected value.
4 is a time chart showing a control example in the case where the current command value detected by the amplifier circuit in the above turbo molecular pump is smaller than the detected value.
5 is a time chart for explaining an example of control by the controller in the turbo molecular pump as described above.
Fig. 6 is a schematic diagram for explaining the effect of the arrangement position of the radical supply port in the above turbo molecular pump.
7 is a longitudinal sectional view of a turbo molecular pump shown as another example of a vacuum pump according to an embodiment of the present invention.

The present invention, in order to achieve the object of providing a vacuum pump capable of effectively discharging by-products by decomposing them into particles and effectively discharging them, includes a housing having an intake port and an exhaust port, and rotatably supported inside the housing. A vacuum pump having a rotor shaft, a plurality of rotary blades fixed to the rotor shaft, and a rotating body rotatable together with the rotor shaft, wherein a plurality of types of radicals can be supplied into the housing, at least one radical It was realized by setting it as the structure provided with the supply port and the radical supply means which supplies the said radical to the said radical supply port.

Example

Hereinafter, an embodiment according to an embodiment of the present invention will be described in detail based on the accompanying drawings. In addition, in the following embodiments, when referring to the number, numerical value, amount, range, etc. of components, they are not limited to the specific number, except when specifically specified and in principle clearly limited to the specific number. , may be greater than or less than a specific number.

In addition, when referring to the shape and positional relationship of components, etc., substantially approximate or similar to the shape, etc. are included, except when it is specifically specified or when it is considered clearly not in principle.

In addition, drawings may be exaggerated by enlarging characteristic parts in order to make the characteristics easier to understand, and it is not limited that the dimensional ratios and the like of constituent elements are the same as those in reality. In cross-sectional views, hatching of some components may be omitted in order to make the cross-sectional structure of the components easier to understand.

In the following description, expressions indicating directions such as up and down, left and right are not absolute, and are appropriate for the posture in which each part of the turbo molecular pump of the present invention is drawn. It has to be changed and interpreted according to the change. Also, the same reference numerals are given to like elements throughout the description of the embodiments.

1 shows an embodiment of a turbo molecular pump 100 as a vacuum pump according to the present invention, and FIG. 1 is a longitudinal sectional view thereof. In the following description, the left side in the left and right direction in FIG. 2 is assumed to be the forward and backward direction of the device, and the right side is referred to as the rear, and the up and down direction is referred to as up and down, and the direction perpendicular to the paper is referred to as left and right.

1, in the turbo molecular pump 100, an intake port 101 is formed at the upper end of an outer cylinder 127 as a cylindrical housing. Then, inside the outer cylinder 127, a plurality of rotor blades 102 (102a, 102b, 102c...), which are turbine blades for suctioning and exhausting gas, are formed radially and in multiple stages on the circumferential portion of the rotating body 103 is provided. A rotor shaft 113 is attached to the center of the rotating body 103, and the rotor shaft 113 is suspended in the air and controlled in position by, for example, five-axis magnetic bearings.

In the upper radial direction electromagnet 104, four electromagnets are arranged in pairs on the X axis and the Y axis. Close to the upper radial electromagnet 104 and corresponding to each of the upper radial electromagnets 104, four upper radial sensors 107 are provided. The upper radial direction sensor 107 uses, for example, an inductance sensor or an eddy current sensor having a conduction winding, and the rotor shaft ( 113) is detected. This upper radial direction sensor 107 is configured to detect the radial displacement of the rotor shaft 113, that is, the rotary body 103 fixed thereto, and send it to the controller 200.

In this controller 200, for example, a compensating circuit having a PID adjusting function generates an excitation control command signal for the upper radial electromagnet 104 based on the position signal detected by the upper radial sensor 107. generated, and the amplifier circuit 150 shown in FIG. 2 (to be described later) excites the upper radial electromagnet 104 based on this excitation control command signal, thereby controlling the upper radial position of the rotor shaft 113 is adjusted

The rotor shaft 113 is made of a material with high magnetic permeability (iron, stainless steel, etc.) and is attracted by the magnetic force of the upper radial electromagnet 104. These adjustments are performed independently in the X-axis direction and the Y-axis direction. In addition, the lower radial electromagnet 105 and the lower radial direction sensor 108 are arranged in the same manner as the upper radial electromagnet 104 and the upper radial sensor 107, so that the radial direction of the lower side of the rotor shaft 113 The position is adjusted to be the same as the radial position of the upper side.

In addition, the axial electromagnets 106A and 106B are arranged by vertically sandwiching a disc-shaped metal disk 111 provided under the rotor shaft 113. The metal disk 111 is made of a high magnetic permeability material such as iron. An axial sensor 109 is provided to detect the axial displacement of the rotor shaft 113, and the axial position signal is sent to the controller 200.

Then, in the controller 200, for example, a compensation circuit having a PID control function, based on the axial position signal detected by the axial sensor 109, the axial electromagnet 106A and the axial electromagnet ( 106B) Each excitation control command signal is generated, and the amplifier circuit 150 excites and controls the axial electromagnet 106A and the axial electromagnet 106B based on these excitation control command signals, thereby generating an axial electromagnet 106A attracts the metal disk 111 upward by magnetic force, and the axial electromagnet 106B attracts the metal disk 111 downward, so that the axial position of the rotor shaft 113 is adjusted.

In this way, the controller 200 appropriately adjusts the magnetic force exerted by the axial electromagnets 106A and 106B on the metal disk 111 to magnetically levitate the rotor shaft 113 in the axial direction, thereby making it non-contact in space. is meant to be maintained. The amplifier circuit 150 for controlling the excitation of the upper radial electromagnet 104, the lower radial electromagnet 105, and the axial electromagnets 106A and 106B will be described later.

On the other hand, the motor 121 includes a plurality of magnetic poles arranged in a circumferential shape so as to surround the rotor shaft 113 . Each magnetic pole is controlled by the controller 200 so as to rotationally drive the rotor shaft 113 through the electromagnetic force acting between them and the rotor shaft 113 . In addition, a rotation speed sensor such as a Hall element, resolver, or encoder, not shown, is attached to the motor 121, and the rotation speed of the rotor shaft 113 is detected by the detection signal of the rotation speed sensor. there is.

Further, for example, a phase sensor (not shown) is mounted near the lower radial direction sensor 108 to detect the rotational phase of the rotor shaft 113. In the controller 200, the position of the magnetic pole is detected using both the detection signals of the phase sensor and the rotational speed sensor.

Rotating blades 102 (102a, 102b, 102c, 102d...) and a plurality of stator blades 123a, 123b, 123c, 123d... are disposed with a slight gap therebetween. The rotor blades 102 (102a, 102b, 102c, 102d...) are inclined by a predetermined angle from a plane perpendicular to the axis of the rotor shaft 113, since each of the exhaust gas molecules is transported downward by collision. is formed

In addition, the stator blades 123 are also formed inclined at a predetermined angle from the plane perpendicular to the axis of the rotor shaft 113 in the same way, and are arranged alternately with the ends of the rotary blades 102 toward the inner side of the outer cylinder 127. there is. And, the outer circumferential edge of the stator blade 123 is supported while being sandwiched between a plurality of staggered stator blade spacers 125 (125a, 125b, 125c, 125d...).

The stator blade spacer 125 is a ring-shaped member, and is made of, for example, a metal such as aluminum, iron, stainless steel, or copper, or an alloy containing these metals as components. An outer cylinder 127 is fixed to the outer periphery of the stator blade spacer 125 with a slight gap therebetween. A base portion 129 is disposed at the bottom of the outer cylinder 127 . An exhaust port 133 and a purge gas supply port 134 are formed in the base portion 129 and communicated with the outside. Exhaust gas that enters the intake port 101 from the chamber side and is transported to the base portion 129 and radicals transported from the radical supply port 201a described later are sent to the exhaust port 133 .

Depending on the purpose of the turbo molecular pump 100, a screw spacer 131 is disposed between the lower portion of the stator blade spacer 125 and the base portion 129. The screw spacer 131 is a cylindrical member made of metal such as aluminum, copper, stainless steel, iron, or an alloy containing these metals as a component, and a plurality of spiral screw grooves 131a are dug in its inner peripheral surface. there is. The spiral direction of the screw groove 131a is the direction in which the molecules of the exhaust gas are transported toward the exhaust port 133 when the molecules of the exhaust gas move in the direction of rotation of the rotating body 103 .

A cylindrical portion 103b hangs down at the lowermost portion of the rotor 103 following the rotor blades 102 (102a, 102b, 102c...). The outer circumferential surface of the cylindrical portion 103b has a cylindrical shape and protrudes toward the inner circumferential surface of the threaded spacer 131, and approaches the inner circumferential surface of the threaded spacer 131 with a predetermined gap therebetween. Exhaust gas transported to the screw groove 131a by the rotary blade 102 and the stator blade 123 is sent to the base portion 129 while being guided to the screw groove 131a.

The base portion 129 is a disk-shaped member constituting the base portion of the turbo molecular pump 100, and is generally made of metal such as iron, aluminum, or stainless steel. Since the base part 129 physically holds the turbo molecular pump 100 and also functions as a heat conduction path, it is preferable to use a metal having rigidity such as iron, aluminum or copper and having high thermal conductivity. do.

In addition, depending on the purpose of the turbo molecular pump 100, a radical supply port 201a, a radical supply valve 201b, and a radical generating source 201c are provided between the fixed blade spacer 125 and the rotary blade 102. A plurality of supply means 201 are arranged. In this embodiment, the radical supply means 201 is provided with two radical supply means 201, a radical supply means 201A and a radical supply means 201B, but one or more radical supply means 201 may be used. .

In addition, the radical supply port 201a of each of the radical supply means 201 (201A, 201B) is at least in the axial direction of the rotating body 103 (the vertical direction of the turbo molecular pump 100 in FIG. It is provided on the exhaust port 133 side rather than the stator blade 102a closest to the intake port 101, that is, between the stator blade 123c and the rotary blade 102d in the embodiment of FIG. Therefore, the radical supply port 201a of each radical supply means 201 has the same height position from the intake port 101, that is, a position substantially equidistant from the intake port 101 in the axial direction, and also in the rotational direction. , they are arranged substantially parallel to the rotor blades 102 and the stator blades 123 with the radical supply direction directed toward the axis of the rotor 103 at approximately equal intervals. Therefore, radicals are respectively taken out from each radical supply port 201a toward the shaft center of the rotating body 103 . In addition, a plurality of radicals taken out from each radical supply port 201a effectively converts a deposit made of by-products that can be granulated through a step using a plurality of radicals to be discharged from the exhaust port 133 together with the radicals. A kind of radical is prepared. Therefore, in this embodiment, it is configured so that radicals of different types can be supplied from each radical supply port 201a. In addition, when only a single radical suffices, the same kind of radical may be supplied from each radical supply port 201a. In addition, even when the supply of different types of radicals is required, the same radical supply port 201a is also used, and different types of radicals are supplied from the same radical supply port 201a, so that the radical supply port 201a Sometimes the number is reduced.

The radical supply valve 201b of each radical supply means 201 is disposed between the radical supply port 201a and the radical generation source 201c, respectively. Each radical supply valve 201b can respectively adjust the supply amount of the radical supplied from the corresponding radical generation source 201c to the radical supply port 201a. Opening and closing control of each radical supply valve 201b is performed by the controller 200 . The controller 200 is constituted mainly by a microcomputer. In the controller 200, in addition to various control circuits, a program capable of controlling the entirety of the turbo molecular pump 100 in a predetermined sequence is integrated and unitized.

As described above, the radical generating source 201c of each radical supply means 201 has a plurality of different types according to the expected by-products so that the by-products that can be granulated through stages can be granulated using a plurality of types of radicals. It is set so that each of the radicals can be supplied. However, when granulation can be made with a single radical, the same kind of radical may be supplied from all the radical generating sources 201c.

Next, in the turbo molecular pump 100 configured as described above, an amplifier circuit 150 for exciting and controlling the upper radial electromagnet 104, the lower radial electromagnet 105, and the axial electromagnets 106A and 106B explain about A circuit diagram of this amplifier circuit 150 is shown in FIG.

2, one end of the electromagnet winding 151 constituting the upper radial electromagnet 104 and the like is connected to the anode 171a of the power source 171 via the transistor 161, and the outer end thereof It is connected to the cathode 171b of the power source 171 through the current detection circuit 181 and the transistor 162 . The transistors 161 and 162 are so-called power MOSFETs, and have a structure in which a diode is connected between their source and drain.

At this time, in the transistor 161, the cathode terminal 161a of the diode is connected to the anode 171a, and the anode terminal 161b is connected to one end of the electromagnet winding 151. In the transistor 162, the cathode terminal 162a of the diode is connected to the current detection circuit 181, and the anode terminal 162b is connected to the cathode 171b.

On the other hand, the diode 165 for current regeneration has its cathode terminal 165a connected to one end of the electromagnet winding 151 and its anode terminal 165b connected to the cathode 171b. Similarly, in the diode 166 for current regeneration, the cathode terminal 166a is connected to the anode 171a, and the anode terminal 166b is connected to the electromagnet winding ( 151) is connected to the other end. The current detection circuit 181 is constituted by, for example, a Hall sensor type current sensor or an electrical resistance element.

The amplifier circuit 150 configured as described above corresponds to one electromagnet. Therefore, when the magnetic bearing is 5-axis control and there are 10 electromagnets 104, 105, 106A, 106B in total, the same amplifier circuit 150 is configured for each of the electromagnets, and 10 for the power supply 171. Two amplifier circuits 150 are connected in parallel.

The amplifier control circuit 191 is constituted by, for example, a digital signal processor section (hereinafter referred to as a DSP section) of a controller, not shown, and this amplifier control circuit 191 includes a transistor 161 , 162) is turned on/off.

The amplifier control circuit 191 compares the current value detected by the current detection circuit 181 (a signal reflecting this current value is referred to as a current detection signal 191c) and a predetermined current command value. Then, based on this comparison result, the size of the pulse width (pulse width time Tp1, Tp2) to be generated within the control cycle Ts, which is one cycle by PWM control, is determined. As a result, the gate drive signals 191a and 191b having this pulse width are output from the amplifier control circuit 191 to the gate terminals of the transistors 161 and 162 .

In addition, when the rotational speed of the rotating body 103 passes through a resonance point during accelerated operation or when a disturbance occurs during constant speed operation, it is necessary to control the position of the rotating body 103 at high speed and with strong force. Therefore, a high voltage of, for example, about 50 V is used as the power source 171 so that a rapid increase (or decrease) of the current flowing through the electromagnet winding 151 is possible. In addition, between the anode 171a and the cathode 171b of the power source 171, a normal capacitor is connected to stabilize the power source 171 (not shown).

In this configuration, when both transistors 161 and 162 are turned on, the current flowing through the electromagnet winding 151 (hereinafter referred to as electromagnet current iL) increases, and when both are turned off, the electromagnet current (iL) decreases.

Also, when one of the transistors 161 and 162 is turned on and the other is turned off, a so-called flywheel current is maintained. And, by flowing the flywheel current through the amplifier circuit 150 in this way, the hysteresis loss in the amplifier circuit 150 is reduced, and power consumption as a whole circuit can be suppressed to a low level. In addition, by controlling the transistors 161 and 162 in this way, high-frequency noise such as harmonics generated in the turbo molecular pump 100 can be reduced. In addition, by measuring this flywheel current with the current detection circuit 181, the electromagnet current iL flowing through the electromagnet winding 151 can be detected.

That is, when the detected current value is smaller than the current command value, as shown in FIG. 3, the transistor 161, for a time corresponding to the pulse width time Tp1, only once in the control cycle Ts (for example, 100 μs), 162) Turn on both. Therefore, the electromagnet current iL during this period increases toward the current value iLmax (not shown) that can flow from the anode 171a to the cathode 171b through the transistors 161 and 162.

On the other hand, when the detected current value is greater than the current command value, as shown in Fig. 4, both transistors 161 and 162 are turned off for a time corresponding to the pulse width time Tp2 only once in the control cycle Ts. do. Therefore, during this period, the electromagnet current iL decreases from the cathode 171b to the anode 171a toward a regenerable current value iLmin (not shown) through the diodes 165 and 166.

In either case, either one of the transistors 161 and 162 is turned on after the pulse width times Tp1 and Tp2 have elapsed. Therefore, the flywheel current is maintained in the amplifier circuit 150 during this period.

In this configuration, when the rotary blade 102 is rotationally driven by the motor 121 together with the rotor shaft 113, the rotary blade 102 and the fixed blade 123 act through the intake port 101. Exhaust gas is aspirated from the chamber. Exhaust gas taken in from the intake port 101 passes between the rotary blade 102 and the stator blade 123 and is transferred to the base portion 129 . At this time, the temperature of the rotor blades 102 rises due to frictional heat generated when the exhaust gas contacts the rotor blades 102 or the conduction of heat generated by the motor 121, and the like. is transmitted to the stator blade 123 side by conduction by gas molecules or the like.

The stator blade spacer 125 is bonded to each other at the outer periphery, and transfers heat received by the stator blade 123 from the rotary blade 102 or frictional heat generated when exhaust gas contacts the stator blade 123 to the outside. do.

In the above description, the screw spacer 131 is arranged so as to correspond to the outer circumference of the cylindrical portion 103b of the rotating body 103, and the screw groove 131a is formed on the inner circumferential surface of the screw spacer 131. Contrary to this, however, in some cases, a screw groove is formed on the outer circumferential surface of the cylindrical portion 103b, and a spacer having a cylindrical inner circumferential surface is disposed around it.

In addition, depending on the purpose of the turbo molecular pump 100, the gas sucked from the intake port 101 passes through the upper radial electromagnet 104, the upper radial sensor 107, the motor 121, and the lower radial electromagnet 105. ), the lower radial sensor 108, the axial electromagnets 106A and 106B, the axial sensor 109, etc., so that the electric part does not intrude into the electric part, the stator column 122 covers the circumference, The inside of this stator column 122 is maintained at a predetermined pressure by the purge gas supplied from the supply port 134 for purge gas.

The supplied purge gas is, for example, between the protective bearing 120 and the rotor shaft 113, between the rotor and the stator of the motor 121, and between the stator column 122 and the inner peripheral side cylindrical portion of the rotor blade 102. It is sent to the exhaust port 133 through the gap of the.

Here, the turbo molecular pump 100 requires identification of the model and control based on individually adjusted unique parameters (eg, various characteristics corresponding to the model). In order to store these control parameters, the turbo molecular pump 100 has an electronic circuit section 141 in its main body. The electronic circuit section 141 is composed of semiconductor memories such as EEP-ROM, electronic components such as semiconductor elements for access thereto, and a board 143 for mounting them. This electronic circuit portion 141 is housed in, for example, a lower portion of a rotational speed sensor (not shown) near the center of the base portion 129 constituting the lower portion of the turbo molecular pump 100, and forms an airtight bottom cover 145. is closed by

By the way, in a semiconductor manufacturing process, some of the process gases introduced into the chamber have the property of becoming solid when the pressure is higher than a predetermined value or the temperature is lower than a predetermined value. Inside the turbo molecular pump 100, the pressure of the exhaust gas is lowest at the intake port 101 and highest at the exhaust port 133. While the process gas is transferred from the inlet port 101 to the exhaust port 133, when the pressure is higher than a predetermined value or the temperature is lower than a predetermined value, the process gas becomes a solid phase and enters the turbo molecular pump 100. is deposited as a by-product.

For example, when ^SiCl ₄ is used as a process gas in an Al etching device, a solid product (eg For example, it can be seen from the vapor pressure curve that AlCl ₃ ) is precipitated and deposited inside the turbo molecular pump 100. As a result, when by-products of the process gas are deposited inside the turbo molecular pump 100, the deposit narrows the pump passage and causes the performance of the turbo molecular pump 100 to deteriorate. In addition, the above-mentioned product was in a situation where it was easy to solidify and adhere in areas where the pressure was high near the exhaust port or in the vicinity of the screw spacer 131.

Therefore, in order to solve this problem, conventionally, a heater not shown or an annular water cooling tube 149 is wound around the outer periphery of the base portion 129 or the like, and further, for example, the base portion 129 ), a temperature sensor (for example, a thermistor) not shown is embedded, and the heater is heated to maintain the temperature of the base part 129 at a constant high temperature (set temperature) based on the signal of the temperature sensor Control of cooling by the water cooling tube 149 (hereinafter referred to as TMS, TMS; Temperature Management System) is performed.

Further, in the turbo molecular pump 100, the gas is solidified and deposited inside the outer cylinder 127 also in the process of compressing the process gas within the turbo molecular pump 100. Therefore, the controller 200 drives the radical supply means 201 between process processes to supply radicals from the radical supply port 201a into the outer cylinder 127 while adjusting the opening and closing of the radical supply valve 201b. It is supplied and flows toward the exhaust port 133. Then, the deposited by-products are reacted and decomposed into radicals to be particles, and discharged from the exhaust port 133 to the outside of the outer cylinder 127 together with the radicals.

5 shows an example of an operation of the controller 200 . In FIG. 5, the opening and closing operation of a chamber valve (not shown) provided between the chamber and the turbo molecular pump 100 and the opening and closing operation of the radical supply valve 201b in the radical supply means 201A shown in FIG. 1 are similarly performed. It is a timing chart showing the opening and closing operations of the radical supply valve 201b in the radical supply means 201B, respectively. In Fig. 5, the Y axis represents the opening/closing operation amount, and the X axis represents the processing time (T). Next, the operation of the controller 200 will be described using the timing chart of FIG. 5 .

The controller 200 performs a discharging process by pulverizing by-products accumulated in the turbo molecular pump 100 into particles at the time of job a in which a chemical reaction process such as etching is performed on a wafer in the chamber.

In this discharge process, first, a chamber valve (not shown) is set from Open to Close to prevent process gas from inside the chamber from flowing into the turbo molecular pump 100 . When it is confirmed that the chamber valve is closed, operation a in the chamber is started. Then, when the time t5 (0.3 minutes) elapses after the chamber valve is closed, the radical supply valve 201b of the radical supply means 201A is switched from closed to open, and the radical supply valve 201b ) is kept open for, for example, time t6 (1 minute). Then, while the radical supply valve 201b is open, the radical of type A is supplied from the radical generating source 201c, and the type A radical is supplied into the outer cylinder 127 from the radical supply port 201a of the radical supply means 201A. A radical of A (e.g., an O radical) is supplied. Also, when supplying radicals, since the controller 200 controls the driving of the motor 121, if there is sufficient time to change the motor rotation, the rotation of the motor 121 is set to a rotation lower than the rated rotation. By switching, the driving of the rotating body 103 can also be operated at a low speed. Then, in a state in which the rotary body 103 is rotating, the type A radical is supplied into the outer cylinder 127 .

The type A radical supplied into the outer cylinder 127 from the radical supply port 201a of the radical supply means 201A passes through the gap between the rotary blade 102 and the stator blade 123 and passes through the outer cylinder ( 127) and is discharged from the exhaust port 133 to the outside of the outer cylinder 127. In addition, when the type A radicals flow through the gap between the rotary blade 102 and the stator blade 123, when the type A radicals reach the deposits deposited in the outer cylinder 127, the type A radicals react with the deposits. By applying large energy, the molecular chains on the surface of the sediment are forcibly cut and decomposed into low-molecular-weight granulated gas. Then, the gas decomposed into low molecular weight and granulated into type A radicals is discharged to the outside through the exhaust port 133 together with the radicals.

In addition, when the supply of the type A radicals supplied into the outer cylinder 127 from the radical supply port (A) 201a of the radical supply means 201A for time t6 (1 minute) is finished, the radical supply of the radical supply means 201A By switching the valve 201b from open to closed again, the supply of type A radicals supplied into the outer cylinder 127 from the radical supply port 201a is stopped.

When the radical supply valve 201b of the radical supply means 201A is switched to Close, after time t7 (0.5 minutes), the radical supply valve (B) 201b of the radical supply means 201B is closed. is switched to open, and the radical supply valve 201b of the radical supply means 201B is kept open for, for example, time t8 (one minute). Then, while the radical supply valve 201b in the radical supply means 201B is open, from the radical generating source 201c in the radical supply means 201B via the radical supply port 201a, the outer cylinder In 127, type B radicals (eg, F radicals) are supplied. Also, when supplying type B radicals, since the controller 200 controls the driving of the motor 121, if there is sufficient time to change the motor rotation, the rotation of the motor 121 is lower than the rated rotation. By switching to low rotation, the driving of the rotating body 103 can also be operated at a low speed. Then, in a state in which the rotating body 103 is rotating, a type B radical is supplied into the outer cylinder 127 .

The type B radicals supplied into the outer cylinder 127 from the radical supply port 201a of the radical supply means 201B pass through the gap between the rotary blade 102 and the stator blade 123 and pass through the outer cylinder ( 127) and is discharged from the exhaust port 133 to the outside of the outer cylinder 127. In addition, when the type B radicals flow through the gap between the rotary blade 102 and the stator blade 123, when the type B radicals reach the deposits deposited in the outer cylinder 127, the type B radicals react with the deposits. By applying large energy, the molecular chains on the surface of the sediment are forcibly cut and decomposed into low-molecular-weight granulated gas. Then, the gas decomposed into low-molecular-weight radicals of type A is discharged to the outside through the exhaust port 133 as in the case of the radical supply means 201A.

In addition, when the supply of the type B radicals supplied into the outer cylinder 127 from the radical supply port 201a of the radical supply means 201B for time t8 (1 minute) is finished, the radical supply valve of the radical supply means 201B 201b is switched from open to closed again to stop the supply of type B radicals supplied into the outer cylinder 127 from the radical supply port 201a.

As a result, the deposits accumulated in the outer cylinder 127 can be reduced by being broken down into particles of A-type radicals and B-type radicals to be removed.

On the other hand, when the radical supply valve 201b of the radical supply means 201B is switched from Open to Close, the operation a of time t1 (3 minutes) in the chamber is also ended.

Then, in the chamber, operation b is started, such as cleaning of the wafer. In operation b, the chamber valve is opened for time t2 (0.5 minutes), then rested for time t3 (1 minute), and opened again for time t4 (0.5 minutes). And while the chamber valve is open, the process gas in the chamber flows into the outer cylinder 127 through the inlet 101 of the turbo molecular pump 100, and the process gas used in the chamber is passed through the turbo molecular pump 100 (outer cylinder (127)) and exhausted from the exhaust port 133.

Thereby, one cycle of the operation of the chamber side and the operation of the turbo molecular pump 100 is ended, and then a series of operations are repeated until the system is stopped.

Therefore, according to the structure of this embodiment, the type A radical flows from the radical supply port 201a of the radical supply means 201A, and the type B radical is discharged from the radical supply port 201a of the radical supply means 201B. Since the radicals of a plurality of types A and B are supplied into the outer cylinder 127 by flowing, even when particles cannot be formed by the reaction of a single radical (type A or type B), the radical supply means 201A By supplying type A and type B radicals from the radical supply port 201a and the radical supply port 201a of the radical supply means 201B, respectively, the by-products first reacted with the type A radicals are converted to the type B radicals. By reacting with a single radical, the deposit made of by-products that cannot be granulated with only single radicals can be effectively converted into gaseous particles and discharged, and cleaning treatment can be performed.

In addition, by supplying radicals into the turbo molecular pump 100, it is possible to supply radicals in an amount necessary and sufficient for reacting by-products in the turbo molecular pump 100, thereby preventing deterioration of the material itself of the turbo molecular pump 100. In addition to being able to suppress it to a minimum, the supply amount of gas required for radical generation can also be suppressed to a minimum.

Further, in the turbo molecular pump 100 of the present embodiment, as shown in FIG. 1 , each radical supply port 201a of the radical supply means 201A, 201B is an intake port in the axial direction of the rotor shaft 113 ( 101) is formed by locating it closer to the exhaust port 133 than the stator blade 102a. That is, the radical supply port 201a is formed between the stator blade 123c and the rotary blade 102d. As a result, when the motions of particles E and F after being formed into particles by reacting with the radicals are schematically shown in FIG. , When part of the particles F that collided with the rotary blade 102d bounced to the intake port 101 side (chamber side), the bounced particles F collided with the stator blade 123c arranged on the intake port 101 side, Heading towards (101) is prevented. Therefore, it is possible to eliminate a factor causing defects such as wafers and the like due to reverse flow of particles F from the rotary blade 102d toward the intake port 101 side into the chamber.

In addition, there is a concern that radicals for granulation may deteriorate the components (mainly aluminum or stainless steel) of the turbo molecular pump 100, but in this embodiment, the radical supply port 201a is directly connected to the turbo molecular pump ( 100) is loaded. Therefore, it is possible to directly supply the least necessary radicals to the turbo molecular pump 100 without being affected by the configuration from the chamber to the exhaust port 133.

Further, by controlling the opening and closing of the radical supply valve 201b, the amount and timing of radicals supplied from the radical generation source 201c from the radical supply port 201a are adjusted under the control of the controller 200. As a control method of the controller 200, methods such as the following (1) to (5) can be considered.

(1) The controller 200 controls the opening and closing of the radical supply valve 201b based on the operation data indicating the operation status of the turbo molecular pump 100. In the case of this control method, the controller 200 itself can judge the state of the vacuum pump from the operation data of the turbo molecular pump 100 and automatically supply radicals into the vacuum pump.

(2) When the current value of the motor 121 that rotates and drives the rotor shaft 113, which is operation data indicating the operation status of the turbo molecular pump 100, exceeds a predetermined threshold value, by-product accumulation is progressing; Upon determining that the supply of radicals is necessary for cleaning the by-product, the controller 200 controls the opening and closing of the radical supply valve 201b. In the case of this control method, when the current value of the motor 121 that rotates and drives the rotor shaft 113, which is operation data, exceeds a predetermined threshold value, the controller 200 determines that supply of radicals is necessary, and automatically As a result, radicals can be supplied into the turbo molecular pump 100.

(3) The current value of the motor 121 that rotates and drives the rotor shaft 113, which is operation data indicating the operating state of the turbo molecular pump 100, is substantially equal to the current value of the motor 121 during no-load operation stored in advance. When the controller 200 controls the opening and closing of the radical supply valve 201b. In the case of this control method, the controller 200 compares the current value of the motor 121 during no-load operation with the current value of the turbo molecular pump 100 with respect to the current value of the turbo molecular pump 100, When the current value of the motor 121 at the time is approximately the same, it is determined that there is no inflow of process gas, and it is determined whether cleaning is performed by the turbo molecular pump alone, and radicals can be automatically supplied into the turbo molecular pump 100.

(4) When the pressure value, which is operation data indicating the operation status of the turbo molecular pump 100, exceeds a predetermined threshold value, the controller 200 detects that accumulation of by-products is progressing, and the by-products are cleaned by removing radicals. determine the need for supply. In the case of this control method, the controller 200 determines the state of the turbo molecular pump 100 from the pressure value of the turbo molecular pump 100, determines whether or not supply of radicals is necessary, and when supply is required, Radicals can be automatically supplied into the turbo molecular pump 100.

(5) When the pressure value of the turbo molecular pump 100, which is operation data indicating the operating state of the turbo molecular pump 100, is approximately the same as the pre-stored pressure value of the vacuum pump during no-load operation, the opening and closing control of the valve is performed. do In the case of this control method, the controller 200 compares the pressure value during no-load operation with the current pressure value of the turbo-molecular pump 100 with respect to the pressure value of the turbo molecular pump 100, When the pressure value of the molecular pump 100 is approximately the same, it is determined that there is no inflow of process gas, and whether or not cleaning is performed by the turbo molecular pump alone, so that radicals can be automatically supplied into the turbo molecular pump 100.

In the turbo molecular pump 100 shown in Example 1, the case of supplying radicals of a plurality of types (type A and type B) has been described, but a single radical such as a type A radical or a type B radical is supplied. When only doing it, you may make it supply the same kind of radical simultaneously from each radical supply port 201a.

7 shows another embodiment of a turbo molecular pump 100, which is a vacuum pump according to the present invention, and FIG. 7 is a longitudinal sectional view thereof. The configuration of the embodiment shown in FIG. 7 is in addition to the radical supply means 201A and radical supply means 201B of the turbo molecular pump 100 shown in FIG. 1, the radical supply means 201A and the radical supply means 201B The lower radical supply means 201C and the radical supply means 201D are provided at a position on the lower side of the rotor shaft 113 in the axial direction from the rotor shaft 113 by a predetermined amount. The configuration of the lower radical supply means 201C and the radical supply means 201D differs only in the height position provided in the outer cylinder 127, and the radical supply means 201A and the radical supply means shown in FIG. 1 are different. Since it is basically the same as the configuration of 201B, like reference numerals are attached to the same components and redundant explanations are omitted.

That is, in the turbo molecular pump 100, which is a vacuum pump shown in FIG. 7, the radical supply port 201a of the upper radical supply means 201A and the radical supply port 201a of the radical supply means 201B are connected to the stator blades. It is formed between (123c) and rotary blade 102d. This is a position located closer to the exhaust port 133 than the stator blade 102a closest to the intake port 101 in the axial direction of the rotor shaft 113. On the other hand, the radical supply port 201a of the lower radical supply means 201D and the radical supply means 201D are also larger than the rotor blade 102j farthest from the intake port 101 in the axial direction of the rotor shaft 113. It is provided between the rotary blade 102j and the screw spacer 131 close to the exhaust port 133 side.

The upper radical supply means 201A and radical supply means 201B, and the lower radical supply means 201C and radical supply means 201D in the turbo molecular pump 100 shown in FIG. 7 are a controller ( 200), radicals of different types A, B, C, and D are respectively treated in a predetermined order during operation a so as to be the same as the timing chart shown in FIG. By pouring off, it is possible to effectively granulate and discharge the sediment composed of by-products capable of being granulated through stages using a plurality of radicals.

In the case of this embodiment shown in Fig. 7, the same effect as in the case of the embodiment shown in Fig. 1 can be obtained. In addition, radicals also have long-lasting effects and short-lived ones. Therefore, by combining two types of radicals, the radicals of type A and type B, which have a long lifespan (life of sustained effect performance), and the radicals of type C and type D, which are shorter than the lifespan of the radicals of type A and type B, When used, the lifespan of type A, type B, type C, and type D radicals can be made the same and can be used efficiently.

Further, in each of the above embodiments, the radical generating power supply of the radical supplying means 201A, the radical supplying means 201B, the radical supplying means 201C, and the radical supplying means 201D and the power supply in the chamber of the semiconductor manufacturing apparatus It is also possible to share . Then, when the radical generating power supply of the radical supply means 201A, the radical supply means 201B, the radical supply means 201C, and the radical supply means 201D is shared with the power supply in the chamber in the semiconductor manufacturing apparatus, the power supply The number of is reduced, and the effect of cost reduction or space reduction can be expected.

In addition, various modifications can be made to the present invention without departing from the spirit of the present invention, and it is natural that the present invention extends to the modified ones.

100: turbo molecular pump
101: intake
102: rotary wing
102a: fixed wing
102c: rotary wing
102d: rotary wing
102j: rotary wing
103: rotating body
103b: cylindrical portion
104: upper radial electromagnet
105: lower radial electromagnet
106A: axial electromagnet
106B: axial electromagnet
107: upper radial sensor
108: lower radial sensor
109: axial sensor
111: metal disk
113: rotor axis
120: protective bearing
121: motor
122: stator column
123: fixed wing
123a: fixed wing
123b: fixed wing
123c: fixed wing
123d: fixed wing
123e: fixed wing
125: fixed wing spacer
127: external cylinder (housing)
129: base part
131: screw spacer
131a: screw groove
133: exhaust
134: supply port for purge gas
141: electronic circuit part
143: substrate
145: bottom cover
149: water cooling tube
150: amplifier circuit
151: electromagnet winding
161: transistor
161a: cathode terminal
161b: anode terminal
162: transistor
162a: cathode terminal
162b: anode terminal
165: diode
165a: cathode terminal
165b: anode terminal
166: diode
166a: cathode terminal
166b: anode terminal
171: power
171a: anode
171b: cathode
181: current detection circuit
191 Amplifier control circuit
191a: gate drive signal
191b: gate drive signal
191c: current detection signal
200: controller
201 radical supply means
201A: radical supply means
201B: radical supply means
201C: radical supply means
201D: radical supply means
201a: radical supply port
201b: valve
201c: radical generating source
A: Kind
B: Kind
E: particle
F: particle
T : processing time
Tp1: Pulse Width Time
Tp2: Pulse Width Time
Ts: control cycle
c : kind
d: kind
iL: electromagnet current
iLmax: current value
iLmin: current value

Claims (14)

A housing having an intake port and an exhaust port;
A rotor shaft rotatably supported inside the housing;
Rotating body having rotary blades fixed to the rotor shaft and rotatable together with the rotor shaft
As a vacuum pump having a,
A vacuum pump characterized by comprising at least one radical supply port capable of supplying a plurality of types of radicals into the housing, and radical supply means for supplying the radicals to the radical supply port. The method of claim 1,
The vacuum pump according to claim 1, wherein the radical supply means includes a radical generating source adapted to the generation of the plurality of types of radicals and a power source for driving the radical generating source. The method of claim 2,
A vacuum pump characterized in that at least a part of the power source for driving the plurality of types of radical generating sources is shared with a power source for controlling the pump. The method of claim 2,
A vacuum pump characterized in that at least a part of the power source for driving the plurality of types of radical generating sources is shared with a power source for plasma generation in the chamber. The method according to any one of claims 2 to 4,
The radical generating source is capable of exchanging electrodes, the power source of the radical generating source has a voltage output variable function, and the generation of various radicals can be realized by exchanging the electrodes and adjusting the voltage output of the power source characterized in that the vacuum pump. The method according to any one of claims 1 to 5,
The vacuum pump according to claim 1, wherein the radical supply means has a valve provided corresponding to each of the radical supply ports and capable of controlling the supply of the radicals supplied from each of the radical supply ports. The method according to any one of claims 1 to 6,
The vacuum pump according to claim 1, wherein each of the radical supply ports is disposed substantially equidistant from the intake port in the axial direction of the rotor shaft. The method of claim 6,
The vacuum pump characterized in that the vacuum pump further includes a controller that controls opening and closing of the valve. The method of claim 8,
The vacuum pump according to claim 1 , wherein the controller controls opening and closing of the valve based on operation data indicating an operating state of the vacuum pump. The method of claim 9,
The controller determines that the accumulation of by-products is progressing and the supply of the radicals is necessary for cleaning the by-products when the current value of the motor that rotates and drives the rotor shaft, which is the operation data, exceeds a predetermined threshold value A vacuum pump, characterized in that for doing. The method of claim 9,
The vacuum pump according to claim 1 , wherein the controller controls opening and closing of the valve when a current value of the motor that rotates and drives the rotor shaft, which is the operation data, is approximately the same as a pre-stored current value of the motor during no-load operation. The method of claim 9,
When the pressure of the vacuum pump, which is the operation data, exceeds a predetermined threshold value, the controller determines that accumulation of by-products is in progress and supply of the radicals is necessary for cleaning the by-products. vacuum pump. The method of claim 9,
The vacuum pump according to claim 1 , wherein the controller performs open/close control of the valve when a pressure value of the vacuum pump, which is the operation data, is approximately the same as a previously stored pressure value of the vacuum pump during no-load operation. A housing having an intake port and an exhaust port;
A rotor shaft rotatably supported inside the housing;
A cleaning system for a vacuum pump having rotary vanes fixed to the rotor shaft and a rotating body rotatable together with the rotor shaft,
A cleaning system for a vacuum pump characterized by comprising at least one radical supply means capable of supplying a plurality of types of radicals into the housing.

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